Directional gun mounting



Oct. 2, 1956 w w ss I 2,764,915

DIRECTIONAL GUN MOUNTING Filed July 1, 1952 3 Sheets-Sheet 1 Oct. 2, 1956 w. WEISS 2,764,915

DIRECTIONAL GUN MOUNTING Filed July 1, 1952 s Sheets-Sheet '2 W/LL/ 14 5/55,

W R QM...

Oct. 2, 1956 W WElSS DIRECTIONAL GUN MOUNTING I5 Sheets-Sheet 3 Filed July 1. 1952 INVE/YI'OI? ML 5/55 DIRECTIONAL GUN MOUNTlNG Willi Weiss, Vernier, near Geneva, Switzerland, assignor to Society Brevets Aero-Mecaniques, S. A., Geneva, Switzerland, a society of France Application July 1, 1952, Serial No. 296,692 Claims priority, application Great Britain July 11, 1951 4 Claims. (Cl. 89-41) This invention relates to gun mountings and like directional mountings, such as Searchlight mountings, and its object is to provide a manpower-operated mounting capable of precise aiming movement at the angular rates required to pick up and follow a target such as a fast aircraft.

The invention will be described as applied to a field mounting for a light anti-aircraft gun but it will be apparcut that the invention is equally applicable to other mountings for example anti-tank or light naval mountings.

Manpower aiming movement of existing mountings is usually elfected by a pair of handwheels or cranks driving through reduction gearings, one to train the mounting in azimuth about the vertical axis and the other to lay the gun by elevation or depression about a horizontal axis. On mountings having a crew of several men, including a trainer and a layer each operating the respective handwheel, this arrangement may be satisfactory but for a light mounting to be aimed by one man who must elfect both the training and laying movements it will be appreciated that for one man to operate two handwheels simultaneously at varying speeds and frequently changing direction is not easy and requires a high degree of co-ordination of hand and mind with much practice to achieve proficiency. There is also the practical difliculty of meeting the requirement that the gun must be capable of being turned rapidly to pick up a target and also slowly but accurately to maintain the gun aimed for the target. To meet this requirement for fast slewing and accurate tracking involves either a two-speed drive or the selection of a compromise gear ratio.

It has also been proposed to train a light gun mounting by means of a pair of pedal crank arms, such as used in bicycles, driving bevel gears around a bevelled ring gear which is secured to a pedestal supporting the mounting. Such a mounting would permit the gunner to apply more strength to training movement but is otherwise subject to the same limitations as handwheel training.

The present invention provides a mounting which can be aimed instinctively by one man at a high or low angular rate as required.

In the aiming movement of a gun or similar mounting the training are of movement about the vertical axis required is much greater than the elevating are about the horizontal axis, a training are of 360 being desirable whereas the elevating arc may be only 90. It will be appreciated therefore that in a manpower mounting the training movement presents the greater problem.

According to the principal feature of the present invention, manpower means for training a gun mounting or like directional mounting comprises gearing by which the mounting can be turned about a normally vertical axis and a pair of pedal levers arranged to be thrust alternatively by the feet of an operator seated on the mounting to drive the gearing through free-Wheel clutch mechanism.

For instinctive aiming, the arrangement is such that to turn the mounting to the right the operator thrusts with his left foot and vice versa, the side of the mounting at which the thrust is made then moving in the direction of the thrust so that the operator experiences a direct response in the same sense as his action.

It is preferred for the clutch mechanism to freewheel automatically, by over-riding or otherwise disengaging when overtaken by the mounting, but the clutch mechanism could be arranged to be engaged and disengaged by selective movement of the operators feet. For fineness of control, friction clutch mechanism is preferred, although a positive mechanism with closely successive engagement positions could be used.

The invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. l is a perspective view of a light anti-aircraft, gun field mounting in the condition for action.

Fig. 2 is a perspective view partly broken away and partly in section of the pedal lever training drive, and

Fig. 3 is a sectional end elevation of the friction clutch in the drive shown by Fig. 2.

As shown in Fig. 1, the mounting has a stout circular base plate 1 to which are hinged tripod legs 2. Road wheels 3 are provided to be raised clear of the ground when the gun is in action as shown. For transport the wheels 3 are lowered and the tripod legs 2 stowed and locked and the gun can then be trailed by the shackle 4. The tripod and transport arrangements do not form part of the present invention and will not be further described.

Fast on the base plate 1 is a circular training rack 5, see Fig. 2, and surrounding the rack 5 and supported by bearings on a central vertical pillar (not shown) of the base plate 1 is a dome 6 which is the central carrier of the training structure of the mountings. The training axis, the axis of rotation of the dome 6, is the axis of the circular rack 5 which is a virtual axis perpendicular to the base plate and thus vertical when the base plate is,

supported horizontally by the tripod legs 2. Side frames 7 integral with the dome 6 provide sockets for the limbs of a tubular U-frame 8 adjustably supporting an operators seat 9. The side frames 7 also support bearings for the trunnion journals 10 of a gun cradle 11 carrying a gun 12 and magazine 13 of a known type.

Upwardly and rearwardly extending arms 14 carry shoulder supports 15 against which the operator can brace himself in moving a pair of hand levers 16 fast with the trunnion journals 10 for laying the gun 12 by elevation or depression of the cradle 11 about the trunnion axis. Instead of being secured directly to the trunnion journals 10, the hand levers 16 could be secured to or form part of a parallel motion linkage for moving the cradle 11. One hand lever carries a trigger for firing the gun and the other may have a brake controllever for arresting laying movement if required during firing.

A telescopic sight 17 is mounted by a parallel motion linkage 18 between the gun cradle 11 and the shoulder supports 15 to move, parallel with the firing axis of the gun 12, about a transverse axis coincident with the'transverse pivotal axis of the operators head. Such parallel motion of a sight is already known.

Journalled in the side frames 7 is apair of pedal levers 19 which can be thrust forwardly by the operators feet, resting on fixed heel supports 20,. to turn the carrier dome 6, and therewith the whole training structure, about the fixed rack 5. The left foot drive for training the mounting is shown in detail in Fig. 2 and it will be understood that the arrangement is duplicated on the other side of the mounting for the other direction of training.

It should be noted that each pedal lever 19 has only a limited arc of angular movement, as compared with the roll rotation of a bicycle-type pedal crank, so that the operator is required only to move his feet forwards and backwards and not around and around.

Fast on the inner end of the journal of each pedal lever 19 is a lever arm 21 to which is pivoted the forward end of a pull rod 22 extending rearwardly into a clutch housing 23 where it is pivoted to the cam-operating lever 24 of an expanding shoe friction clutch very similar in construction to an expanding shoe brake for an automobile wheel. As shown the lever 24 is carried fast on the outer end of a cam shaft 25 journalled in a plate 26 closing a drum 27 fast on the stub shaft 2%; of a bevel wheel 29. The cam shaft 25 carries a cam 30 between the opposed ends of a pair of shoes 31 having frictional linings 32 to bear against the inside cylindrical surface of the drum 27 when thrust apart by turning of the cam 30. The shoes 31 are pivoted on an anchor pin 33 carried by the plate 26 and have return springs 34.

Forward and rearward movement of the camoperating lever 24 is limited by stops 35 and 36 respectively on the plate 26, and the plate 26, 'and therewith the pedal lever 19, is normally maintained in a medial position by a doubleacting centralising spring 37 (see Fig. 3) in a tangential cylinder 38 extending from the clutch housing 23. The centralising spring 37 is a helical compression spring embracing a push-pull rod 39 connected at its outer end by a pin and slot pivot 40 to the plate 26 and extending slidingly through upper and lower collars 41 and 42 confining the ends of the spring 37 and thrust thereby against the ends of the cylinder 38 which has a domed outer end cap 38 to allow protrusion of the outer end of the rod 39.

It will be seen from Fig. 2 that the clutch drum closing plate 26 is journalled on the end of the stub shaft 28 and can turn relatively thereto so long as the shoes 31 are not gripping the clutch drum 27. When the pedal lever 19 is thrust forward however the cam 30 is turned to spread the shoes 32 which grip the drum 27 which thereupon moves with the pedal lever and turns the bevel wheel 29 to drive a bevel pinion 43 fast on a vertical pinion shaft 44 the lower end of which carries a pinion 45 which rides round the fixed rack 5 on the base plate 1 and thereby trains the carrier dome 6, and the whole training structure carried thereby, to the left or right according to which pedal lever has been thrust. If the thrust on the respective pedal lever is slow and steady themounting trains about the rack 5 steadily proportional to the degree ofpedal movement.

If however thepedal lever is thrust strongly the mounting gains momentum and, after the pedal lever has reached its forward extremity, drives back through the pinion shaft and bevel wheel drive and clutch drum and closing plate which latter turns relatively to the camoperating lever, pivotally held by the pull rod pivoted to the pedal lever, so that the cam is turned relatively to the ends of the shoes which disengage from the clutch drum and the mounting then free-wheels in the direction of the strong pedal thrust. Thus fast training, or socalled slewing, of the mounting can be effected for picking up a target.

Should one pedal lever be thrust while the operator is applying pressure to the other pedal lever so that the clutch which is not being directly driven is engaged, rotation of the mounting will drive back through such clutch entraining the respective pedal lever to move rearwardly and thus disengage the clutch to allow the mounting to slew in the direction of thrust provided that the operator does not maintain undue pressure on the back-driven pedal lever.

It will thus be appreciated that the operator by a strong thrust with either foot can slew the mounting in either direction, can then use moderate pressure with the other foot to brake the movement and then steadily train the mounting round by differential pressure with his feet, both clutches being engaged by initial pressure with both feet. In this training procedure the movement of the mounting is directly proportional to difierential pressure, and thus to equal and opposite movement, of the operators feet as though the pedal levers were at opposite ends of a rudder bar or transverse bar with direct positive training drive.

I claim:

1. In a directional mounting comprising a base, a training structure on said base, a pair of pedal levers on said training structure, and training motion transmission gear means connected between said pedal levers and said base, the combination with said transmission gear means of free-wheel clutch means to transmit thrust from said pedal levers through said transmission gear means and to free-wheel to interrupt transmission of training motion through said transmission gear means back to said pedal levers.

2. A directional mounting as claimed in claim 1, said free-wheel clutch means being friction clutch means.

3. A gun mounting comprising a base, a training structure on said base for movement about a training axis perpendicular to said base, a pair of pedal levers pivoted on said training structure for limited angular movement relatively to said training structure, and training motion transmission gear means connected between said pedal levers and said base, whereby thrust on a pedal lever will through said gear means effect training motion of said training structure, said gear means including free-wheel clutch means operable on the momentum of said training structure overcoming the thrust of a pedal lever to interrupt transmission of training motion through said gear means back to said pedal levers to elfect slewing of the training structure in the direction of thrust.

4. A directional mounting comprising a base, a circular rack fast about an axis perpendicular to said base on said base, a training structure carrier rotatably mounted on said base coaxially with said rack, a pinion journalled in said carrier and meshing with said rack, transmission gear means mounted on said carrier and drivin'gly connected to said pinion to turn saidpinion to train said carrier about said rack, a pair of pedal levers pivoted on said carrier for limited angular movement relatively to said carrier, and a pair of automatic free-wheel friction clutch means mounted on said carrier and each connected on one side to said transmission gear means and on the other side respectively to one of said pedal levers.

References Cited in the file of this patent UNITED STATES PATENTS 1,543,263 Methlin June 23, 1925 1,700,902 Prieur Feb. 5, 1929 1,855,069 Ricordel Apr. 19, 1932 2,452,076 Spencer Oct. 26, 1948 2,486,526 Gross Nov. 1, 1949 FOREIGN PATENTS 820,994 France Aug. 17, 1937 

